[ maternally inherited balanced reciprocal translocation in a mentally retarded dysmorphic girl]

A 29 years old girl with various dimorphic features including short stature and webbed neck with mild to moderate mental retardation was referred to our center for chromosome investigation. Her parents were first cousins. The mother has had two previous miscarriages, one deceased son [12 years old] with apparently similar abnormal features to the proband with congenital heart problems, and one normal son [27 years old]. The patient, her mother and the brother, all were found to have an apparently balanced reciprocal translocation between the long arms of chromosomes 4 and 10. The breakpoint on chromosome 4 is at the distal end [4q35], while for chromosome 10, it is proximal to the centromere [10q11.2]. FISH studies using multiprobe subtelomeric specific probes as well as whole chromosome paints for chromosomes 4 and 10 were carried out in search of a genetic imbalance. The FISH results revealed no telomeric rearrangements and confirmed the balanced reciprocal translocation between chromosomes 4 and 10. To date, this is the first reported case of t[410][q35q11.2]

[Prenatal diagnosis of chromosomal abnormalities by amniocentesis: report of 261 cases]

Amniocentesis is a technique for detection of chromosomal abnormalities in the unborn fetuses. The technique is being applied to the all high risk pregnancies, mostly in advanced maternal ages and abnormal results in the 1st or 2nd trimester pregnancies. In current situation, first trimester screening is being done in the 11 to 13 weeks and 6 days of gestation, and mid-trimester screening [between weeks 15 to 20]. We report the result of our samples in this article. 261 pregnancies were followed and screened by 1st and 2nd trimester screening by Iranian Fetal Foundation protocols in an 18 months period [from January 2007 to July 2008]. Advanced maternal ages [35 years and more], or detected a balanced structural chromosomal abnormalities in one of the parents were indications for amniocentesis in this group. Amniocentesis was performed in the 261 cases during the mentioned period. In all of the culture tubes [100%] cell growth was successful. Mean of the time for screening and reporting the results was 12 days. Twelve affected fetuses [4.6%] were detected. The most common abnormalities were Down's syndrome and balanced translocation. First and second trimester screening is recommended to all pregnancies by international FMF protocol. Whenever the results showed that the pregnancy is prone to the risk then amniocentesis is highly recommended to detect chromosomal abnormalities